When eight-year-old Huang Na went missing in October 2004, it sparked a massive three-week search across the island.
Over 100 volunteers from Crime Library - a group known for tracking down missing people - were mobilised to put up posters, distribute leaflets, and comb Singapore for the Chinese national, described as having big eyes and shoulder-length hair and last seen in a blue jacket.
When her tiny, decomposing body was later found in Telok Blangah Hill Park, volunteers, who included students and housewives, wept openly.
"Missing cases should not be taken lightly. We had to mobilise more volunteers to search, as we were running against time. It was a lot of hard work," said Crime Library founder Joseph Tan.
Gone are the days when search parties were mobilised to look for missing people. Now, this search has gone online - and the chances of finding missing people are surprisingly higher, volunteer groups told The Straits Times.
Crime Library, for instance, has not had to activate its volunteers in ground searches for the past five years. In its heyday, it would receive a few calls each day asking for help to find missing people.
"We haven't had to utilise volunteers like what we used to do," said Mr Tan. "Many concerned people now share missing person posts on social media, and it doesn't take long before a missing person is found. But if a search is required, our volunteers are willing to do so."
Online appeals for missing people are not uncommon. They come with photos of the missing and include their usual hangouts, the attire they were last seen in, as well as family members' contact details.
Earlier this month, a 13-year-old boy went missing and was found three days later. An appeal for information made its rounds on social media over those few days, with hundreds taking to Facebook to share news of the boy, described as around 1.7m tall and wearing blue-framed spectacles.
Facebook pages like Singapore Missing People and Reunite Missing Children have helped expand search efforts for the missing. Both pages have over 1,000 followers each.
Reunite Missing Children was created in February last year to help disseminate appeals for missing children, particularly those with special needs. The group, set up by several parents, also offers updates such as when a child is last seen.
Ms Sun Meilan, one of its founders, said special needs kids may not be able to ask for help. "Finding a missing child can be like a wild goose chase. And most parents don't know where to start looking."
Without a search team, the group relies on social media to tap the larger community to keep a lookout. Some netizens have chipped in, offering clues to a child's whereabouts.
Police said inquiries are immediately conducted when a missing person report is received. These include screening the person against police databases and checking with institutions and hospitals.
Besides disseminating information for officers on the ground to look out for the missing person, they may also issue appeals for information from the public on various platforms, including social media.
There is no minimum time required for the missing person to have lost contact with family members before a report can be lodged.
A spokesman said the viral nature of social media allows netizens to share the information from the police, "thereby providing a multiplier effect to our efforts".
Ms Sun urged the public to spare a few minutes to share missing person posts on social media. "A lot of times, we don't know if we've made a difference," she said. "But we can still do something to help."